This invention relates generally to machines used in the process of fusing polyolefin pipe and more particularly concerns facers used to prepare the opposed ends of two polyolefin pipes for butt fusion.
Situations in which a facer might be of use in extending a polyolefin pipe in a tight working space, such as adjacent a wall or ceiling, are not uncommon. And accessibility to such a tight working space may be further complicated by the presence of other pipes, equipment and supporting structure in the vicinity. Unfortunately, however, known facers for polyolefin pipes of mid-range diameter are poorly designed for such applications.
Most known mid-range diameter polyolefin pipe facers are simply too heavy to be lifted by hand into such tight working spaces. For example, facers for 24″ OD polyolefin pipe typically weigh between 200 and 400 pounds.
Many facers are designed to face a range of pipe sizes and so their output speeds (RPM) are selected to handle the largest diameter or thickest wall pipe in their pipe range. Consequently, when they are used to face a pipe with a smaller diameter or thinner wall, they operate slower than necessary and do not make full use of their available horsepower.
Most known facers are designed to be mounted on carriages of only one size and their carriages are designed to be modified to permit the same facer to face a range of pipe sizes. Such facers must be sized for the largest pipe diameter in their range. Consequently, when used to face runs of smaller diameter pipe, the carriage size prevents the runs of pipe from being as close together as might otherwise be possible.
And most known facers produce polyolefin ribbons that can wrap tightly around the ends of the opposed pipes during facer rotation. The ribbons can block the operator's view of the pipe ends and can build up sufficiently to require periodic stoppage of the facing process to clear the ribbons. Furthermore, the ribbons can fall into, tangle in and be hard to clean out of the fusion machine.
It is, therefore, an object of this invention to provide a polyolefin pipe facer that is of use in extending a polyolefin pipe in a tight working space. Another object of this invention is to provide a polyolefin pipe facer that reduces the impact of a facer's weight on its utility for use in a tight working space. A further object of this invention is to provide a polyolefin pipe facer that reduces the impact of a facer's size on its utility for use in a tight working space. It is also an object of this invention to provide a polyolefin pipe facer that affords greater accessibility to tight working spaces than known facers. Yet another object of this invention is to provide a polyolefin pipe facer that makes full use of its available horsepower for more than one size of pipe. An additional object of this invention is to provide a polyolefin pipe facer that enables the running of multiple sizes of pipe closer together than is possible with known facers. And it is an object of this invention to provide a polyolefin pipe facer that controls the dispersion of polyolefin ribbons produced by the facer.